The etymology of the word is uncertain. It was in use in English around 1850 and attested in 1886.
The most romantic story surrounding this word says that "gadget" actually comes from the French company Gaget-Gauthier which made miniatures of the Statue of Liberty (1886) in order to promote and finance this project by Frédéric Auguste Bartholdi.
The book "Je me souviens du 17éme Arrondissement" by Sylvie Bonin (1994) specifies (page 78) that Mr. Gaget, one of the directors of the Parisian workshop for the construction of the Statue of Liberty (rue de Chazelles, Paris 17), took 20-centimeter-high replicas of the statue to the USA. The name "Gaget" was written on the base. The Americans call the statue "gadget."
Source: Wikipedia
